Chris Hogg Wrote in message:
On Tue, 14 Mar 2017 09:53:27 -0000 (UTC), Tim+
wrote:

Would be nice if some of this turned out to be true.
http://spectrum.ieee.org/energywise/...the-end-of-oil

Tim

Interesting. I see they're claiming the battery will charge in minutes
rather than hours.

Say a typical car petrol tank holds 12 gallons. 1 gallon of petrol has
an energy equivalent of 33.4kWh
https://en.wikipedia.org/wiki/Gasoli...lon_equivalent

So a typical car petrol tank contains an energy equivalent of about
400kWh. If that were to be replaced by a battery storage system, which
was wanted to be recharged in say 5 minutes (one twelfth of an hour),
as is done now with a petrol filling system, that would require a
power input of 4800kW (400x12). At 1000 amps that would be 4800 volts
(assuming my logic and numbers are correct, which they may not be!).

I'd be interested to see the forecourt of the future!

But I imagine things would no longer be done that way. If those
batteries are truly reliable, then an exchange system would probably
be the way things would go.

Or you'd charge it at home overnight?

What are the relative efficiencies of petrol vs electric powerplants?

--
Jim K


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

On 14/03/2017 11:47, jim wrote:
Chris Hogg Wrote in message:
On Tue, 14 Mar 2017 09:53:27 -0000 (UTC), Tim+
wrote:

Would be nice if some of this turned out to be true.
http://spectrum.ieee.org/energywise/...the-end-of-oil

Tim

Interesting. I see they're claiming the battery will charge in minutes
rather than hours.

Say a typical car petrol tank holds 12 gallons. 1 gallon of petrol has
an energy equivalent of 33.4kWh
https://en.wikipedia.org/wiki/Gasoli...lon_equivalent

So a typical car petrol tank contains an energy equivalent of about
400kWh. If that were to be replaced by a battery storage system, which
was wanted to be recharged in say 5 minutes (one twelfth of an hour),
as is done now with a petrol filling system, that would require a
power input of 4800kW (400x12). At 1000 amps that would be 4800 volts
(assuming my logic and numbers are correct, which they may not be!).

I'd be interested to see the forecourt of the future!

But I imagine things would no longer be done that way. If those
batteries are truly reliable, then an exchange system would probably
be the way things would go.

Or you'd charge it at home overnight?

What are the relative efficiencies of petrol vs electric powerplants?

Petrol is around 25%-30% vs nearly 100% for electric.

In article ,
GB wrote:
What are the relative efficiencies of petrol vs electric powerplants?

Petrol is around 25%-30% vs nearly 100% for electric.

And of course doesn't have to idle in traffic jams or use energy to be
restarted. And won't use vastly more fuel when warming up.

Be interesting to know a ballpark figure for the real world differences in
energy storage needed.

--
*Why is the word abbreviation so long? *

Dave Plowman London SW
To e-mail, change noise into sound.

On 14/03/2017 12:07, Chris Hogg wrote:

Car petrol engines around about 20% max, a bit more for diesel.
Probably triple that for electric cars, so by implication only half
the equivalent tank capacity needed. But that still leaves some pretty
hefty amps/volts needed for charging.
See https://www.fueleconomy.gov/feg/evtech.shtml for some numbers.



Surely, triple = one-third capacity needed?

If you add in that electric cars tend to have regenerative braking and
so on, it gets better still.

One way petrol engines score is that they use waste heat for warming the
passengers.

On 14/03/2017 13:42, Chris Hogg wrote:
On Tue, 14 Mar 2017 12:27:17 +0000, GB
wrote:

On 14/03/2017 12:07, Chris Hogg wrote:

Car petrol engines around about 20% max, a bit more for diesel.
Probably triple that for electric cars, so by implication only half
the equivalent tank capacity needed. But that still leaves some pretty
hefty amps/volts needed for charging.
See https://www.fueleconomy.gov/feg/evtech.shtml for some numbers.



Surely, triple = one-third capacity needed?

Yes, absolutely correct. The initial figures I found suggested a
factor of two difference, but later I found the factor of three, but I
omitted to correct that bit.


Sorry to be pedantic.

Anyway, it seems that an electric car with a fully charged 100kWh
battery should be able to do much the same range as a petrol car on a
single tank. Glancing at Tesla, they are claiming about 300 mile range
for their cars with the biggest batteries. That would suit me fine, as 4
hours is my absolute maximum drive.

"GB" wrote in message
news
On 14/03/2017 13:42, Chris Hogg wrote:
On Tue, 14 Mar 2017 12:27:17 +0000, GB
wrote:

On 14/03/2017 12:07, Chris Hogg wrote:

Car petrol engines around about 20% max, a bit more for diesel.
Probably triple that for electric cars, so by implication only half
the equivalent tank capacity needed. But that still leaves some pretty
hefty amps/volts needed for charging.
See https://www.fueleconomy.gov/feg/evtech.shtml for some numbers.



Surely, triple = one-third capacity needed?

Yes, absolutely correct. The initial figures I found suggested a
factor of two difference, but later I found the factor of three, but I
omitted to correct that bit.


Sorry to be pedantic.

Anyway, it seems that an electric car with a fully charged 100kWh battery
should be able to do much the same range as a petrol car on a single tank.
Glancing at Tesla, they are claiming about 300 mile range for their cars
with the biggest batteries. That would suit me fine, as 4 hours is my
absolute maximum drive.

it's not that simple though, is it

if you were visiting me for the weekend there is nowhere you could recharge
your car when you arrive

so your battery has to be good for the round trip

(FTAOD I live on on of these "modern" estates where nobody has a drive and
everyone parks on the road. And I live on the second floor so running a
cable out of the window isn't practical either)

tim

In article ,
tim... wrote:
Anyway, it seems that an electric car with a fully charged 100kWh
battery should be able to do much the same range as a petrol car on a
single tank. Glancing at Tesla, they are claiming about 300 mile
range for their cars with the biggest batteries. That would suit me
fine, as 4 hours is my absolute maximum drive.

it's not that simple though, is it

if you were visiting me for the weekend there is nowhere you could
recharge your car when you arrive

so your battery has to be good for the round trip

Plenty live many miles from a filling station too.

--
*It sounds like English, but I can't understand a word you're saying.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
GB wrote:
Yes, absolutely correct. The initial figures I found suggested a
factor of two difference, but later I found the factor of three, but I
omitted to correct that bit.


Sorry to be pedantic.

Anyway, it seems that an electric car with a fully charged 100kWh
battery should be able to do much the same range as a petrol car on a
single tank. Glancing at Tesla, they are claiming about 300 mile range
for their cars with the biggest batteries. That would suit me fine, as 4
hours is my absolute maximum drive.

Think you have to be even more careful with the claimed range of an
electric car than you do with a maker's petrol MPG figures. ;-)

--
*When the chips are down, the buffalo is empty*

Dave Plowman London SW
To e-mail, change noise into sound.

On 14/03/2017 15:35, Chris Hogg wrote:

Anyway, it seems that an electric car with a fully charged 100kWh
battery should be able to do much the same range as a petrol car on a
single tank. Glancing at Tesla, they are claiming about 300 mile range
for their cars with the biggest batteries. That would suit me fine, as 4
hours is my absolute maximum drive.

The point I wanted to make was that in order to charge an electric car
battery in times comparable with filling the tank with petrol, you'd
need an awful lot of amps at an awful lot of volts.


Tesla claims that you can get a 50% charge in 20 minutes at one of their
super-fast chargers. That sounds like around 100kW = 400 amps at 240v,
which seems rather high.

On 14/03/17 19:03, Chris Hogg wrote:
On Tue, 14 Mar 2017 17:32:29 +0000, GB
wrote:

On 14/03/2017 15:35, Chris Hogg wrote:

Anyway, it seems that an electric car with a fully charged 100kWh
battery should be able to do much the same range as a petrol car on a
single tank. Glancing at Tesla, they are claiming about 300 mile range
for their cars with the biggest batteries. That would suit me fine, as 4
hours is my absolute maximum drive.

The point I wanted to make was that in order to charge an electric car
battery in times comparable with filling the tank with petrol, you'd
need an awful lot of amps at an awful lot of volts.


Tesla claims that you can get a 50% charge in 20 minutes at one of their
super-fast chargers. That sounds like around 100kW = 400 amps at 240v,
which seems rather high.

Yes, I agree with those figures. OK if you want to stop at a service
station and pop in for a coffee while you wait, but at busy times
there's often a queue for the normal petrol pumps, and they have a
fairly rapid turnover, so what it would be like with a twenty minute
wait I shudder to think.

Exactly. But you can charge a li-ion battery - if its designed for it -
in about 6 minutes, Gets a bit hot of course.


--
"Women actually are capable of being far more than the feminists will
let them."

On Tuesday, 14 March 2017 20:28:28 UTC, The Natural Philosopher wrote:
On 14/03/17 19:03, Chris Hogg wrote:
On Tue, 14 Mar 2017 17:32:29 +0000, GB
wrote:

On 14/03/2017 15:35, Chris Hogg wrote:

Anyway, it seems that an electric car with a fully charged 100kWh
battery should be able to do much the same range as a petrol car on a
single tank. Glancing at Tesla, they are claiming about 300 mile range
for their cars with the biggest batteries. That would suit me fine, as 4
hours is my absolute maximum drive.

The point I wanted to make was that in order to charge an electric car
battery in times comparable with filling the tank with petrol, you'd
need an awful lot of amps at an awful lot of volts.


Tesla claims that you can get a 50% charge in 20 minutes at one of their
super-fast chargers. That sounds like around 100kW = 400 amps at 240v,
which seems rather high.

Yes, I agree with those figures. OK if you want to stop at a service
station and pop in for a coffee while you wait, but at busy times
there's often a queue for the normal petrol pumps, and they have a
fairly rapid turnover, so what it would be like with a twenty minute
wait I shudder to think.

Exactly. But you can charge a li-ion battery - if its designed for it -
in about 6 minutes, Gets a bit hot of course.

Which will add to global warming if 1000s are doing it day in day out.
Might be a few cool explosions too.

In article ,
Chris Hogg wrote:
Yes, I agree with those figures. OK if you want to stop at a service
station and pop in for a coffee while you wait, but at busy times
there's often a queue for the normal petrol pumps, and they have a
fairly rapid turnover, so what it would be like with a twenty minute
wait I shudder to think.

But you wouldn't need a traditional filling station - underground tanks
etc. The charging points could just be in the ordinary car park.

--
*If you tell the truth, you don't have to remember anything.*

Dave Plowman London SW
To e-mail, change noise into sound.

On 15/03/2017 08:07, Chris Hogg wrote:
On Wed, 15 Mar 2017 00:22:44 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Chris Hogg wrote:
Yes, I agree with those figures. OK if you want to stop at a service
station and pop in for a coffee while you wait, but at busy times
there's often a queue for the normal petrol pumps, and they have a
fairly rapid turnover, so what it would be like with a twenty minute
wait I shudder to think.

But you wouldn't need a traditional filling station - underground tanks
etc. The charging points could just be in the ordinary car park.

Indeed you could, and that's probably how it would work. Say fifty
charging points, each with a 1 MW capacity charger for rapid charging,
is quite a lot of power to be supplied.

And that's only for the cars...


50 x 100kW would be 5MW in total. They might need more charging stations
if electric cars really catch on. But say 20MW range should do it for
the foreseeable future for a very large motorway service station.

To put that in perspective, an ordinary suburban street (100 houses) has
a combined mains input of 2-3MW. If my arithmetic is right! So, 50
charging stations in constant use would need the same input mains as a
couple of longish suburban streets.

More likely, they could have more charging stations than 50 served by a
5MW mains input, as they wouldn't all be charging at the same time.

In article ,
Chris Hogg wrote:
On Wed, 15 Mar 2017 00:22:44 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Chris Hogg wrote:
Yes, I agree with those figures. OK if you want to stop at a service
station and pop in for a coffee while you wait, but at busy times
there's often a queue for the normal petrol pumps, and they have a
fairly rapid turnover, so what it would be like with a twenty minute
wait I shudder to think.

But you wouldn't need a traditional filling station - underground tanks
etc. The charging points could just be in the ordinary car park.

Indeed you could, and that's probably how it would work. Say fifty
charging points, each with a 1 MW capacity charger for rapid charging,
is quite a lot of power to be supplied.

And that's only for the cars...

True. Has anyone worked out how much extra generating capacity we'd need
if every vehicle was electric?

--
*A backward poet writes inverse.*

Dave Plowman London SW
To e-mail, change noise into sound.

On 14/03/17 15:35, Chris Hogg wrote:
On Tue, 14 Mar 2017 14:18:57 +0000, GB
wrote:

On 14/03/2017 13:42, Chris Hogg wrote:
On Tue, 14 Mar 2017 12:27:17 +0000, GB
wrote:

On 14/03/2017 12:07, Chris Hogg wrote:

Car petrol engines around about 20% max, a bit more for diesel.
Probably triple that for electric cars, so by implication only half
the equivalent tank capacity needed. But that still leaves some pretty
hefty amps/volts needed for charging.
See https://www.fueleconomy.gov/feg/evtech.shtml for some numbers.



Surely, triple = one-third capacity needed?

Yes, absolutely correct. The initial figures I found suggested a
factor of two difference, but later I found the factor of three, but I
omitted to correct that bit.


Sorry to be pedantic.

Not a problem. Happy to be corrected.

Anyway, it seems that an electric car with a fully charged 100kWh
battery should be able to do much the same range as a petrol car on a
single tank. Glancing at Tesla, they are claiming about 300 mile range
for their cars with the biggest batteries. That would suit me fine, as 4
hours is my absolute maximum drive.

The point I wanted to make was that in order to charge an electric car
battery in times comparable with filling the tank with petrol, you'd
need an awful lot of amps at an awful lot of volts.

well one or the other. to charge a 100kWh battery in six minutes is a
MW...Sort of what a small train takes pulling out of Waterloo.


But motorway service stations with substations of their own cope with that.

4000A at 250V. DC.

Probably feed in 11KV instead. only 90A then..


--
Truth welcomes investigation because truth knows investigation will lead
to converts. It is deception that uses all the other techniques.

The Natural Philosopher wrote:

On 14/03/17 15:35, Chris Hogg wrote:
On Tue, 14 Mar 2017 14:18:57 +0000, GB
wrote:

On 14/03/2017 13:42, Chris Hogg wrote:
On Tue, 14 Mar 2017 12:27:17 +0000, GB
wrote:

On 14/03/2017 12:07, Chris Hogg wrote:

Car petrol engines around about 20% max, a bit more for diesel.
Probably triple that for electric cars, so by implication only half
the equivalent tank capacity needed. But that still leaves some pretty
hefty amps/volts needed for charging.
See https://www.fueleconomy.gov/feg/evtech.shtml for some numbers.



Surely, triple = one-third capacity needed?

Yes, absolutely correct. The initial figures I found suggested a
factor of two difference, but later I found the factor of three, but I
omitted to correct that bit.


Sorry to be pedantic.

Not a problem. Happy to be corrected.

Anyway, it seems that an electric car with a fully charged 100kWh
battery should be able to do much the same range as a petrol car on a
single tank. Glancing at Tesla, they are claiming about 300 mile range
for their cars with the biggest batteries. That would suit me fine, as 4
hours is my absolute maximum drive.

The point I wanted to make was that in order to charge an electric car
battery in times comparable with filling the tank with petrol, you'd
need an awful lot of amps at an awful lot of volts.

well one or the other. to charge a 100kWh battery in six minutes is a
MW...Sort of what a small train takes pulling out of Waterloo.


But motorway service stations with substations of their own cope with that.

4000A at 250V. DC.

Probably feed in 11KV instead. only 90A then..

I suspect something in the 1.5 to 2.5kV range would be easier to handle
with standard precautions and no excessive distortion of the car to
provide sufficient spacing.



--

Roger Hayter

In message , Chris Hogg
writes
Car petrol engines around about 20% max, a bit more for diesel.
Probably triple that for electric cars, so by implication only half the
equivalent tank capacity needed. But that still leaves some pretty
hefty amps/volts needed for charging. See
https://www.fueleconomy.gov/feg/evtech.shtml for some numbers.

Did anyone else hear the piece on Radio 4 a few days ago about UPS in
Birmingham?

Apparently they have converted 6 or 7 of their delivery vehicles to
electric power and have been very happy with the results.

But they can't convert any more because 6 or 7 is all they can charge
overnight. That uses the total supply available to their industrial
site.
--
Bill